A variable resonator is provided which comprises signal conductor 13 formed on top side surface of dielectric substrate 12, ground conductor layer 11 formed on back side surface thereof and switches 14, wherein signal conductor comprises a plurality of first conductor lines 13-1 and second conductor line 13-2 connected with all of first conductor lines, each first conductor line has a width larger than that of second conductor line to thereby a signal path through which high-frequency electric signal passes and which is longer than length of second conductor line is provided, switches 14 are connected to the ends of first conductor lines, whereby selectively opening and closing switches will electrically disconnect and interconnect interspaces between ends of first conductor lines to thereby vary length of signal path and thus change resonance frequency.

Variable resonator and variable phase shifter

PURPOSE: To prepare the titled compound economically, by reacting an aromatic nitro compound and a lower a aliphatic alcohol or a phenol in liquid phase in the presence of a catalyst containing platinum-group metal with CO preparaed by specific method, and circulating and reusing the exhaust gas of the reaction. CONSTITUTION: An aromatic nitro compound (e.g. nitrobenzene) and a lower aliphatic alcohol (e.g. methanol) or a phenol are made to react with CO in liquid phase in the presence of a catalyst containing a platinum-group metal (e.g. Pd, Rh, etc.) at 100W250°C to obtain an aromatic urethane. The amount of the alcohol or phenol is 2W400mol, pref. 5W50mol per 1mol of the nitro group of the aromatic nitro compound. The CO gas is prepared by passing a mixed gas containing CO 2 and O 2 through the layer of coke heated at ≥900°C. The exhaust gas obtained after the completion of the urethane-forming reaction is recycled to the above coke layer. COPYRIGHT: (C)1982,JPO&Japio

Preparation of aromatic urethane

PURPOSE:To improve the reliability and to attan small size and light weight by inserting respectively a switch circuit between each midpoint of two lines having a characteristic being equivalent to an input/output impedance among 4 lines and ground. CONSTITUTION:The switch circuits 22, 23 are coupled respectively between the midpoints 20, 21 of the 2 lines 14, 15 having the impedance equivalent to the input/output impedance among the 4 lines 12-15 and ground. Through the constitution above, when the switch circuits 22, 23 are opened, they act like a hybrid ring, the which a reception power of one side of two input terminals 16, 17 is synthesized and the power is outputted from the other terminal 19, and in grounding the switch circuits 22, 23, the transmission power of the other terminal 19 is outputted from the terminal 17 and also the circuit constitution is very simple, then the reliability is improved and small size and light weight are attained.

High frequency switching circuit

An urethane compound is produced in high yield under mild conditions by reacting a formamide compound with dimethyl carbonate in the presence of basic anion exchange resin as a catalyst or by reacting an amine compound with dimethyl carbonate in the presence of basic anion exchange resin as a catalyst and methyl formate. Separation and recovery of the catalyst and purification of the urethane compound can be carried out very readily, and since control of water content is not particularly required in this invention, an amine compound and dimethyl carbonate of poor quality can be used.

Process for producing urethane compound

In a quadrature hybrid circuit which has first and second two-port circuits 11 and 12 inserted between I/O ports P1 and P2 and between I/O ports P4 and P3, respectively, and third and fourth two-port circuits inserted between I/O ports P1 and P4 and between I/O ports P2 and P3, respectively, and which is configured so that under the condition that the I/O ports P1 to P4 are matched, a high-frequency signal fed via the I/O port P1 is divided between the I/O ports P2 and P3 and the divided two signals are output 90 DEG out of phase with each other but no signal is provided to the I/O port P4, there are provided SPST switches 7 and 8 responsive to external control to control electromagnetic connections or coupling across a plane of symmetry 5 of the quadrature hybrid circuit passing through intermediate points of symmetry 23 and 24 of the third and fourth two-port circuits 21 and 22.

90 degrees hybrid circuit

PURPOSE:To prepare the titled compound in high yield, by reacting an aromatic nitro compound with carbon monoxide and excess organic compound containing hydroxyl group in the presence of a catalyst using a specific organic solvent. CONSTITUTION:An aromatic carbamic acid ester is synthesized by reacting an aromatic nitro compound (e.g. nitrobenzene) with a hydroxyl-containing organic compound (e.g. methanol, phenol, etc.) and carbon monoxide in the presence of a catalyst (e.g. Pd, Pt, etc.). The amount of the hydroxyl-containing organic compound is adjusted to 1.1-15mol per 1 equivalent of the nitro group of the aromatic nitro compound, and the reaction is carried out in the presence of 0.1- 15pts.vol., based on 1pt.vol. of the hydroxyl-containing organic compound, of an organic solvent (e.g. hydrocarbons, halogenated hydrocarbons, nitriles, ethers, etc.). High reaction activity can be achieved by the use of said solvent, and accordingly, the corrosive action of the reaction system can be mitigated by reducing the concentration of the catalyst.

Yamamoto Iwao

Papers

Preparation of aromatic carbamic acid ester